Rack server system and control method thereof

ABSTRACT

A rack server system and a control method thereof are provided. The rack server system establishes a communication link for communicating with a battery backup unit. The battery backup unit is connected to a power input port of the rack server system, and includes a number of battery modules connected with each other in parallel. The rack server system controls the battery backup unit to perform validity test on a first battery module during a first period and to perform validity test on a second battery module during a second period, wherein the first period and the second period are not overlapped with each other.

This application claims the benefit of Taiwan application Serial No. 100126882, filed Jul. 28, 2011, the subject matter of which is incorporated herein by reference.

TECHNICAL FIELD

The disclosure relates in general to a rack server system and a control method thereof, and more particularly to a rack server system which controls a battery backup unit via a communication interface to perform validity test and a control method thereof.

BACKGROUND

A battery backup unit may replace the uninterruptible power supply (UPS). Under the circumstances when abnormality (such as power off, power insufficient, power interference or surge) occurs to a main power supplied to a rack server system, the battery backup unit supplies power to the rack server system to maintain normal operation; and a power supply apparatus such as a power generator is activated to provide backup power. In general, the battery backup unit is used for maintaining necessary operations for critical commercial or precision apparatuses, such as rack server systems, switches, to prevent data loss lest the business might suffer from tremendous loss or other unexpected consequences.

Validity of the battery backup unit has much to do with system stability. If the battery backup unit fails due to aging or other factors, the battery backup unit may not maintain the normal operation of the rack server system when abnormality occurs to the main power supplied to the rack server system, and data may be lost. To assure the validity of the battery backup unit, validity test such as discharge test is performed on the battery backup unit periodically to obtain whether the battery has sufficient power.

However, if abnormity, such as power off, occurs to the main power supplied to the rack server system when the battery backup unit is in discharge test, power stored in the battery backup unit may be nearly used up and the battery backup unit may be unable to maintain the normal operation of the rack server system. Meanwhile, the rack server system may have stability problem which may lead to data loss. Therefore, how to reduce the risk of data loss of the rack server system has become a prominent task for the industries.

SUMMARY OF THE DISCLOSURE

The disclosure is directed to a rack server system and a control method thereof which reduce the risk of data loss of the rack server system when a battery backup unit is in validity test.

According to an example of the present disclosure, a control method applicable to a rack server system is provided. The rack server system establishes a communication link for communicating with a battery backup unit. The battery backup unit is connected to a power input port of the rack server system, and includes a number of battery modules connected with each other in parallel. The rack server system controls the battery backup unit to perform a validity test on a first battery module during a first period and to perform a validity test on a second battery module during a second period, wherein the first period and the second period are not overlapped with each other.

According to another example of the present disclosure, a rack server system is provided. The rack server system includes a power input port, a communication interface and a control unit. The power input port is connected to a battery backup unit. The battery backup unit includes a number of battery modules connected with each other in parallel. The communication interface establishes a communication link for communicating with the battery backup unit. The control unit is connected to the communication interface. The control unit controls the battery backup unit to perform a validity test on a first battery module during a first period and to perform a validity test on the validity of a second battery module during a second period, wherein the first period and the second period are not overlapped with each other.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosed embodiments, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a flowchart of a control method according to one embodiment of the disclosure;

FIG. 2 shows a block diagram of an example of a rack server system and a battery backup unit according to one embodiment of the disclosure;

FIG. 3A and FIG. 3B show timing diagrams of an example of communication between the rack server system and the battery backup unit of FIG. 2; and

FIG. 4 shows a block diagram of another example of a rack server system and a battery backup unit according to one embodiment of the disclosure.

DETAILED DESCRIPTION OF THE DISCLOSURE

A rack server system and a control method thereof are disclosed in a number of embodiments below. In some embodiments, a battery backup unit includes a number of battery modules connected in parallel. The battery modules are controlled by a rack server system via a communication interface; and validity test such as discharge test is performed on the battery modules in time-sharing. In other words, when a part of the battery modules are under validity test, other part of the battery modules are not under validity test and are ready to provide power to the rack server system. Thus, the risk of data loss of the rack server system is reduced.

Referring to FIG. 1, a flowchart of a control method according to one embodiment of the disclosure is shown. The control method is for use in the rack server system. At step S110, the rack server system establishes a communication link for communicating with a battery backup unit. The battery backup unit is connected to a power input port of the rack server system. The battery backup unit includes a number of battery modules connected in parallel. At step S120, the rack server system controls the battery backup unit to test validity of a first battery module of the battery backup unit during a first period. At step S130, the rack server system controls the battery backup unit to test validity of a second battery module of the battery backup unit during a second period. The first period and the second period are not overlapped with each other. The two non-overlapping periods refer that the two battery modules of the battery backup unit are under validity test in time-sharing to reduce the risk of data loss of the rack server system.

Referring to FIG. 2, a block diagram of an example of the rack server system and the battery backup unit according to one embodiment of the disclosure is shown. The rack server system 200 may be realized by such as but not limited to a cloud computing rack server system. The rack server system 200 such as includes a number of servers (not illustrated) inside a rack. The rack server system 200 at least includes a power input port 210, a communication interface 220, and a control unit 230. In FIG. 2, the rack server system 200 of the present example is illustrated as a basic model for convenience of elaborating the embodiments of the disclosure, and in fact, rack server system should include other circuits not illustrated here.

The power input port 210 is connected to a battery backup unit 300. For example, the power input port 210 may be realized by a DC power input port for receiving DC power. The power input port 210 may include two or more input ends for receiving DC power having different polarities or different levels such as receiving power from an AC/DC power supply or receiving power from the battery backup unit 300. When abnormality occurs to a main power supplied the rack server system 200, the power input port 210 feeds the power from the battery backup unit 300 to the system 200, such that the system 200 is powered for maintaining normal operations.

The communication interface 220 establishes a communication link for communicating with the battery backup unit 300. In some embodiments, the communication interface 220 is a wireless communication interface such as Bluetooth, wireless fidelity (Wi-Fi), or other wireless communication standards or wireless communication protocols. In some other embodiments, the communication interface 220 is such as a wire communication interface, which may be connected to the battery backup unit 300 via a communication bus 240 of the rack server system 200. The communication bus 240 is such as an RS232 bus, an I²C bus, a controller area network (CAN) bus, or other bus.

The control unit 230 is connected to the communication interface 220. Via the communication interface 220, the control unit 230 controls the battery backup unit 300 to perform validity test on the battery backup unit 300. In the present embodiment of the disclosure, the battery backup unit 300 includes a number of battery modules 310-1˜310-n connected in parallel as indicated in FIG. 2. The control unit 230 plans or arranges execution times and execution sequence of validity tests on the battery modules 310-1˜310-n for reducing risk of data loss of the rack server system.

In some embodiments, the control unit 230 may control the battery backup unit 300 to test validity of the battery modules 310 one by one, sequentially or non-concurrently. For example, the control unit 230 may control the battery backup unit 300 so as to test validity of the first battery module 310-1 during a first period and to test validity of a second battery module 310-2 during a second period, wherein the first period and the second period are not overlapped with each other. The validity test periods on other battery modules 310-3˜310-n may be arranged similarly. Thus, during any test period, the rack server system 200 may be powered by battery modules not under validity test, and the risk of data loss of the rack server system may thus be reduced.

In some other embodiments, the control unit 230 may control the battery backup unit 300 to test validity of a part of the battery modules (such as two or more battery modules) during a first period and test validity of another part of the battery modules (such as another two or more battery modules) during a second period. Thus, during any test period, the rack server system 200 may be powered by battery modules not under validity test, and risk of data loss of the rack server system can thus be reduced.

For the battery backup unit 300, each of the battery modules 310-1-310-n includes similar elements. Let the battery module 310-1 be taken for example. The battery module 310-1 includes a power supply port 311-1, a DC-to-DC converter 312-1, and a battery 313-1. The power supply port 311-1 is coupled to the power input port 210 of the rack server system 200. The DC-to-DC converter 312-1 is connected between the battery 313-1 and the power supply port 311-1 for converting a voltage of the battery 313-1 into a voltage for the rack server system 200. The battery 313-1 is such as a secondary battery or other type. In some implementation examples, the battery 313-1 is such as a lithium battery. In some other implementation examples, the battery 313-1 is such as a reusable battery, a rechargeable battery or a replaceable battery.

The arrangement of a number of battery modules increases the power supply stability of the battery backup unit 300. In other words, if one battery module fails, other battery modules of the battery backup unit 300 still provides power to the rack server system 200. Thus, stability of the rack server system 200 is kept so as to reduce risk of data loss of the rack server system.

Moreover, for the battery backup unit 300, via the validity test, the control unit 230 knows whether the battery backup unit 300 fails due to aging or other factors, so as to assure validity of the battery backup unit 300. In an implementation example, the validity test on the battery backup unit 300 is such as discharge test. During the discharge test, the battery backup unit 300 increases its output voltage so as to provide energy to the rack server system 200. In other implementation example, if the battery backup unit 300 uses lithium battery, then the validity test is a learning curve test which records the relationship between usage time and voltage. However, the disclosure is not limited to such exemplification, and the validity test on the battery backup unit 300 is based on the types of the battery modules or on user request.

Referring to FIG. 3A and FIG. 3B, timing diagrams of an example of the communication between the rack server system and the battery backup unit of FIG. 2 are shown. The disclosure is further elaborated below in conjunction with FIG. 2 and FIGS. 3A and 3B.

At step S310, the rack server system 200 establishes a communication link for communicating with the battery backup unit 300. Correspondingly, in step S410, the battery backup unit 300 communicates with the rack server system 200.

In step S312, the rack server system 200 reads previous data to obtain result(s) of previous validity test(s) and execution time(s) on the battery backup unit 300. Correspondingly, in step S412, the battery backup unit 300 provides previous test data to the rack server system 200. Test data is stored in a memory of the battery backup unit 300, such as a non-volatile memory. Data read by the rack server system 200 are information such as the execution time and the result of a previous validity test on the battery modules 310-1˜310-n, or other information such as lifespan, manufacturer, manufacture date, and electrical characteristics.

In step S314, the rack server system 200 plans or arranges the execution times and test sequence of validity tests on the battery modules 310-1˜310-n. The rack server system 200 such as plans or arranges the execution times and sequence of validity tests on the battery modules 310-1˜310-n according to the read data. For example, considering system stability, the execution times of validity tests on the battery modules 310-1˜310-n are neither concurrent nor overlapped with each other. The execution sequences of validity test on the battery modules 310-1˜310-n are such as determined according to previous execution times. For example, the earlier the previous test time on a battery module, the higher sequence priority of the validity test on the battery module. The execution time of validity tests on the battery modules 310-1˜310-n are determined according to previous execution results of the battery modules 310-1˜310-n. For example, the battery module(s) which was/were failed in the previous validity test may be not tested so as to reduce the total test time.

In step S316, the rack server system 200 sends a command to notify the battery backup unit 300 for a validity test. Correspondingly, in step S416, the battery backup unit 300 receives the command to begin validity test. For example, the battery backup unit 300 increases the output voltage to release energy.

In step S318, the rack server system 200 receives a return data indicating the test result. Correspondingly, in step S418, the battery backup unit 300 determines the state of the battery module(s) under test. If the test result indicates “pass”, then the method proceeds to step S422, the battery backup unit 300 charges the battery module(s) passed in the test, and after charging finishes, the battery backup unit 300 transmits the return data and the method proceeds to step S318. If the test result indicates “fail”, then the method proceeds to step S420, the battery backup unit 300 controls an indicator such as a light emitting diode (LED) to generate an indication signal such as a light signal indicating failure of the battery module(s) under test. Some embodiments may further include other steps for generating the return data indicating the test result or steps for storing the test result to a memory (not shown) of the battery backup unit 300.

In step S320, the rack server system 200 determines the result of validity test on the battery module(s) according to the return data. If the test result indicates “fail”, then the method proceeds to step S322. If the test result indicates “pass”, then the method proceeds to step S324.

In step S322, the rack server system 200 generates the indication signal, such as a light signal, an audio signal, or a signal for displaying a message on a screen, to notify or remind the user to replace the battery module. Then, the method proceeds to step S324.

In step S324, the rack server system 200 stores the results of validity test. Via the communication interface 220, the test result is transmitted to the control unit 230 and may be further stored in a memory (not shown) of the control unit 230 or other memory not shown.

In step S326, the rack server system 200 determines a default loading according to the results of validity tests on the battery modules 310-1˜310-n. The default loading determines efficiency of the rack server system 200 when abnormality occurs to the main power supplied to the rack server system 200. The default loading such as determines the loading of the rack server system when abnormality occurs to the main power.

In some embodiments, the default loading determines the number of normal operating servers of the rack server system when abnormality occurs to the main power. For example, under full-loading, the rack server system 200 may activate all servers so as to operate at high efficiency and at high power consumption. Under half-loading, the rack server system 200 activates half of the servers and shut down another half of the servers safely, and both efficiency and power consumption are reduced.

In some embodiments, the default loading determines operation frequency of a processor of each server of the rack server system when abnormality occurs to the main power. For example, under full-loading, the processor of each server of the rack server system 200 operates at highest operation frequency, high efficiency but high power consumption. Under half-loading, the operation frequency of the processor of each server of the rack server system 200 is half, and efficiency and power consumption are reduced.

The above default loading for determining the number of the active servers and/or for determining the operation frequency of the processor of the server is for exemplification purpose not for limiting the disclosure. The default loading may also be other parameters relating to the efficiency, loading, or power consumption of the rack server system when abnormality occurs to the main power.

In some embodiments, when a battery module is failed in the validity test, the rack server system 200 may reduce the default loading. The default loading is such as reduced according to the number of the failed battery modules. Suppose 10 battery modules are used, and the initial default loading is full-loading. When one battery module fails, the default loading may be reduced by 1 tenth as 9-tenth loading. When a half of the battery modules fails, the default loading may be reduced by 5 tenths as half-loading. Thus, when abnormality occurs to the main power of the rack server system 200, the rack server system 200 avoids operating at high efficiency and/or high power consumption. Thus, the stability of the rack server system is kept so as to reduce the risk of data loss of the rack server system.

Referring to FIG. 4, a block diagram of another example of a rack server system and a battery backup unit according to one embodiment of the disclosure is shown.

In the present example, the rack server system 400 includes a power input port 410, a system communication interface 420, and a system control unit 430. The operations of the rack server system 400 are similar to that of the rack server system 200 of FIG. 2, and the similarities are not repeated here.

The battery backup unit 500 includes a number of battery modules 510-1˜510-n connected in parallel, and further includes a battery communication interface 520 and a battery control unit 530. The battery control unit 530 and the rack server system 400 communicate with each other and may implement the above control method.

The battery control unit 530 may execute a part of operations of the system control unit 430. For example, the battery control unit 530 receives a notification from the system control unit 430 and controls the battery modules 510-1˜510-n to perform validity test in time-sharing. In another example as indicated in step S314, the battery control unit 530 may plan and arrange the execution time and sequence of validity test.

No matter the rack server system controls the battery backup unit to perform validity test or the rack server system notifies the control unit of the battery backup unit to perform validity test, those are possible embodiments of the disclosure as long as battery modules of the battery backup unit are tested in time-sharing.

According to the rack server system and the control method thereof of the present embodiment of the disclosure, the battery backup unit includes a number of battery modules connected with each other in parallel and the battery modules are controlled by the rack server system via the communication interface to be tested such as a discharge test in a time-sharing manner, so as to reduce the risk of data loss of the rack server system.

In some embodiments, with the configuration of the battery backup unit (which is modularized) and the communication interface, the rack server system notifies the battery modules to be under test (i.e. system control). The advantage of system control is that all loading conditions are taken into consideration to avoid interrupt of power supply during test or due to failure of the battery module. In cooperation with the battery backup unit which is modularized, the system controls the battery modules under validity test at different periods (i.e. in time-sharing), so as to keep system stability.

In some other embodiments, the power consumption of the rack server system when abnormality occurs to the main power may be determined according to the results of validity tests on the battery modules, so as to avoid the rack server system operating at high efficiency and high power consumption. Thus, the risk of data loss of the rack server system may be further reduced.

It will be appreciated by those skilled in the art that changes could be made to the disclosed embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that the disclosed embodiments are not limited to the particular examples disclosed, but is intended to cover modifications within the spirit and scope of the disclosed embodiments as defined by the claims that follow. 

1. A control method applicable to a rack server system, comprising: establishing a communication link between the rack server system and a battery backup unit, wherein the battery backup unit is connected to a power input port of the rack server system, and comprises a plurality of battery modules connected with each other in parallel; controlling the battery backup unit by the rack server system to perform a validity test on a first battery module of the battery modules during a first period; and controlling the battery backup unit by the rack server system to perform a validity test on a second battery module of the battery modules during a second period, wherein the first period and the second period are not overlapped with each other.
 2. The control method according to claim 1, further comprising: receiving a return data from the battery backup unit to the rack server system; and determining a result of the validity test on the first battery module by the rack server system according to the return data.
 3. The control method according to claim 1, wherein the validity test on the first battery module or the second battery module includes a discharge test.
 4. The control method according to claim 1, further comprising: determining a default loading by the rack server system according to results of validity test on the battery modules, wherein the default loading determines efficiency of the rack server system when abnormality occurs to a main power supplied to the rack server system.
 5. The control method according to claim 4, wherein when the validity test on one of the battery modules shows failed, the rack server system reduces the default loading.
 6. The control method according to claim 5, wherein the rack server system reduces the default loading according to a number of failed battery modules.
 7. The control method according to claim 4, wherein the default loading determines a loading of the rack server system when abnormality occurs to the main power.
 8. A rack server system, comprising: a power input port connected to a battery backup unit, wherein the battery backup unit comprises a plurality of battery modules connected with each other in parallel; a communication interface establishing a communication link for communicating with the battery backup unit; and a control unit connected to the communication interface for controlling the battery backup unit to perform a validity test on a first battery module of the battery modules during a first period and controlling the battery backup unit to perform a validity test on a second battery module of the battery modules during a second period, wherein the first period and the second period are not overlapped with each other.
 9. The rack server system according to claim 8, wherein each battery module comprises; a power supply port connected to the power input port of the rack server system; a battery; and a DC-to-DC converter connected between the battery and the power supply port.
 10. The rack server system according to claim 9, wherein the battery is a secondary battery.
 11. The rack server system according to claim 8, further comprising; a communication bus connecting the communication interface to the battery backup unit.
 12. The rack server system according to claim 8, wherein the rack server system further receives a return data from the battery backup unit, and determines a result of the validity test on the first battery module according to the return data.
 13. The rack server system according to claim 8, wherein the validity test on the first battery module or the second battery module includes a discharge test.
 14. The rack server system according to claim 8, wherein the rack server system further determines a default loading according to results of validity tests on the battery modules, and the default loading determines efficiency of the rack server system when abnormality occurs to a main power supplied to the rack server system.
 15. The rack server system according to claim 14, wherein when the first battery module is failed in the validity test, the rack server system reduces the default loading.
 16. The rack server system according to claim 15, wherein the rack server system reduces the default loading according to a number of failed battery modules.
 17. The rack server system according to claim 14, wherein the default loading determines a loading of the rack server system when abnormality occurs to the main power.
 18. The rack server system according to claim 8, wherein the battery backup unit further comprises; another communication interface connected to the battery modules; and another control unit connected to the another communication interface and controlled by the rack server system for controlling the battery modules to perform the validity test. 